samba - May 2024 - winbind: does it actually depend on nmbd? and network-online?

On Thu, 2 May 2024 13:44:47 +0300
Michael Tokarev via samba <samba at lists.samba.org> wrote:
> Hi!
> 
> In packaging/systemd/winbind.service, there's this ordering:
> 
> After=network.target nmb.service
> 
> Does winbind really need nmbd running?
Well, no and yes ;-)

No, if you are running Samba as an AD Unix domain member without SMBv1
(in which case, you do not need nmbd at all), but if you are still
running an NT4-style domain, then you need nmbd to provide NetBIOS
Browsing.
> 
> Another interesting dependency here.  nmb.service (in the same
> directory) has
> 
> Wants=network-online.target
> After=network.target network-online.target
> 
> Note nmbd needs network to be online.  While winbind only needs
> network to be up.  If winbind requires nmbd, who in turn requires
> network to be online, winbind will be started only with online
> network.  If we drop winbind dependency on nmbd here, winbind will
> be started earlier, before network is online.
> 
> Does winbind requires network to be online or just up?
No idea about that, perhaps Jeremy will know.

Rowland

02.05.2024 14:17, Rowland Penny via samba wrote:
> On Thu, 2 May 2024 13:44:47 +0300
> Michael Tokarev via samba <samba at lists.samba.org> wrote:
> 
>> Hi!
>>
>> In packaging/systemd/winbind.service, there's this ordering:
>>
>> After=network.target nmb.service
>>
>> Does winbind really need nmbd running?
> 
> Well, no and yes ;-)
> 
> No, if you are running Samba as an AD Unix domain member without SMBv1
> (in which case, you do not need nmbd at all), but if you are still
> running an NT4-style domain, then you need nmbd to provide NetBIOS
> Browsing.
Okay, I suspected it will be a bit more difficult.  Let's put it this
way: does winbind in non-AD environment really need NetBIOS Browsing to
work?  Or if it does, where the requirement is coming from?  Or maybe,
can it be avoided, like, by providing LMHOSTS entry?

Winbind being dependent on UDP-based, quite fragile, browsing sounds like
a good way to disaster.

And yes, I know full well that these days, nmbd and netbois aren't used.

Thanks,

/mjt

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On Thu, May 02, 2024 at 12:17:43PM +0100, Rowland Penny via samba
wrote:
>On Thu, 2 May 2024 13:44:47 +0300
>Michael Tokarev via samba <samba at lists.samba.org> wrote:
>>
>> Note nmbd needs network to be online.  While winbind only needs
>> network to be up.  If winbind requires nmbd, who in turn requires
>> network to be online, winbind will be started only with online
>> network.  If we drop winbind dependency on nmbd here, winbind will
>> be started earlier, before network is online.
>>
>> Does winbind requires network to be online or just up?
>
>No idea about that, perhaps Jeremy will know.
What's the difference between "online" and "up" ?